Convertible ladder.



H. MUTE.

CONVERTIBLE LADDER.

APPLIOATION FILED MAY 4, 1912.

1,070,908, Patented Aug. 19, 1913.

2 SHEETS-SHEET 1.

.Zizzrezzzar H. MOTE.

CONVERTIBLE LADDER.

APPLIOATION FILED MAY 4, 1912 1,070,908, Patented Aug. 19, 1913.

2 SHEETS-SHEET 2.

21/172255555' fizz/Emm- M55: 2 ZFZ E @2W'gZA COLUMBIA PLANOGRAPH(0.,WAsmNu'roN D c UNITED STATES PATENT OFFICE.

HORACE MOTE, OF CLEVELAND, OHIO, ASSIGNOR TO THE STEELBACK LADDERCOMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

CONVERTIBLE LADDER.

Application filed May 4, 1912.

-T 0 all whom it may concern Be it known that I, HORACE MOTE, a subjectof the King of England, residing at Cleveland, in the county of Cuyahogaand State of Ohio, have invented certain new and useful Improvements inConvertible Ladders, of which the following is a speci fication.

My invention relates to improvements in convertible ladders, and has forits object the construction of ladder-members which may be united ininterchangeable relation, for the purpose of forming a step ladder, anextension ladder or a scaffold or tower ladder. These are formed of twotypes of ladder-members, one of which is a step-carrying section, andthe other a rung-carrying section, which may respectively be united toform the difierent classes of ladders named. My said improvementcontemplates the construction of such ladder-members provided withuniting brackets having stationary retaining parts thereon, adapted tosecure the ladder-members in different angular and extended relation toeach other.

The embodiment of my invention may be briefly described as consisting ofa step ladder section, which may be of ordinary construction, butequipped adjacent to its upper end, with two laterally positionedbrackets, respectively secured to the side pieces of the ladder and thetop step; each of said brackets being equipped with two hooks positionedin different planes. Associated therewith, is a second ladder-member ofsubstantially the same length as the step ladder section, but providedwith rungs and side pieces mitered at one end; any of said rungs beingadapted for insertion within the hooks of the bracket, in order toconvert the ladder to the forms mentioned above.

Further details of my improvement may be more readily explained andunderstood by making reference to the accompanying drawings, whereinFigure 1. is a fragmentary view in vertical sections, showing the upperportion of a step ladder and the bracket-member embodying my invention.Fig. 2. is a view in side elevation of said bracket-member. Fig. 3. is afragmentary view in vertical section, of an extension ladder, embodyingmy invention. Fig. 4. is a perspective view of the ladders combined toform a tower-ladder.

Specification of Letters Patent.

Patented Aug. 19, 1913.

Serial No. 695,236.

The figures have been drawn upon different scales to bring out thevarious features of improvement in condensed form.

I have employed the same character of reference to designate similarparts throughout the several figures of the drawings.

Preferably the side pieces a of the step ladder section are somewhatspread at the base; being united by the transverse steps b and the topstep 1). Between the top step b and the next step b, the two brackets,a, formed of malleable iron, are secured respectively to the side piecesa and the under and upper faces of said steps, by means of wood screws.These brackets 0 are symmetrical and are cast from malleable iron inright and left patterns, to brace the upper portion of the step ladder,and accommodate the second ladder-member. Referring specifically to thefigures of the drawing, showing one of said brackets, it is seen that itcomprises an upright d provided with screw holes for securing it to theside piece; a slotted head 6 adapted to engage the top step b; a slottedfoot f, adapted to engage the second step b, and two hooks g 71,respectively positioned in dilferenthorizontal and vertical planes foraccommodating the different rungs of the ladder-member. The secondladder-member comprises two arallel side pieces i, mitered at their en si and united by the usual rungs 2'; each of said rungs adapted to fitwithin the hooks g h of the bracket. From these simple ladder-members,or duplicates thereof, in case the scaffold, or tower ladder is desired,the three above mentioned types of ladder may be quickly and easilyformed without the aid of tools.

As shown in Fig. 1, the step ladder section and the rung ladder-membermay be united by inserting the upper rung i" of the latter within thehooks g. The laddermembers are accordingly disposed at an angle, withthe mitered ends 11 of the side pieces i bearing against the rear facesof the side pieces a, in order to form a strong and rigid step ladder.Again, by placing the rung ladder-members parallel, with any of therungs 1'" supported by the hooks h, an extension ladder of variablelength is provided as shown in Fig. 3. Finally, by uniting two rungladder-members by means of spring clamps la embracing their side pieces71' above and below, and supporting their corresponding rungs 2'"respectively from the hooks g of two opposed step ladder sec tions, asshown in Fig. 4, a tower ladder of variable height may be constructed,either for use alone, or in association with another similar ladder, forsupporting a scaffold plank.

For convenience of designation, I have indicated the step laddersections upon drawings, by the reference character Z, and coacting rungladder-members, by the reference character m.

My improved means for convertibly uniting the ladder sections, comprisesessentially, two stationarily secured, symmetrical castings or forgingspositioned adjacent to the upper end of a ladder section, at either sidethereof; each affording two hooks, or recessed portions adapted torespectively embrace a ladder rung in two different vertical andhorizontal planes, substantially as shown. The hooks 9, it will beobserved, support the rung ladder member against movement, eithervertically or away from the step-ladder section, when engaging a rung ofthe former. In addition, each bracket-member preferably is provided witha head and base portion respectively attached by means of slot-engagingscrews, to the two upper steps of the ladder-section, whereby a muchmore rigid structure is attained. Said bracket, moreover, preferablyaffords an offset shoulder at which is adapted to engage the rear of theside piece and a recess f adjacent to the lower hook 72 which bearsagainst the step b, as best shown in Figs. 1 and 2, thus insuring a firmrigid support for the upper ladder-member of an extension ladder.

It will be apparent that the rungs of the extension ladder, willregister with the steps of the step ladder, which is the pre ferredarrangement, rat-her than to make an irregularly spaced connectionbetween the two ladder-members.

Having now described apparatus embodying my invention and the principalutility thereof, I claim as new, and desire to secure by Letters Patent,the following A combination ladder, comprising a stepladder section anda rung ladder-member of approximately equal lengths, and two bracketsstationarily secured to the step next adjacent to the top of saidstep-section and close to the side pieces thereof, each of said bracketsbeing provided with a rung-supporting recess in alinement with the step,and adjacent thereto, and with a hook intermediate of the two uppersteps and so distanced from the rear face of the step-section as toreceive a rung of the rung ladder-member standing vertically, while thestep-section is at the usual inclination with the vertical; said hookbeing formed to support the rung against movement either vertically oraway from the step-section, substantially as set forth.

In testimony whereof I do now affix my signature in the presence of twowitnesses.

HORACE MOTE.

WVitncsses:

C. V. PUTNAM, ALBERT LYNN LAWRENCE.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

